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<tr class="t-nv-h1"><td colspan="5"> 类</td></tr>
<tr class="t-nv"><td colspan="5"><div class="t-nv-ln-table"><div><a href="../basic_regex.html" title="cpp/regex/basic regex"><span class="t-lines"><span>basic_regex</span></span></a></div><div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx11">(C++11)</span></span></span></div></div></td></tr>
<tr class="t-nv"><td colspan="5"><div class="t-nv-ln-table"><div><a href="../sub_match.html" title="cpp/regex/sub match"><span class="t-lines"><span>sub_match</span></span></a></div><div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx11">(C++11)</span></span></span></div></div></td></tr>
<tr class="t-nv"><td colspan="5"><div class="t-nv-ln-table"><div><a href="../match_results.html" title="cpp/regex/match results"><span class="t-lines"><span>match_results</span></span></a></div><div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx11">(C++11)</span></span></span></div></div></td></tr>
<tr class="t-nv-h1"><td colspan="5"> 算法</td></tr>
<tr class="t-nv"><td colspan="5"><div class="t-nv-ln-table"><div><a href="../regex_match.html" title="cpp/regex/regex match"><span class="t-lines"><span>regex_match</span></span></a></div><div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx11">(C++11)</span></span></span></div></div></td></tr>
<tr class="t-nv"><td colspan="5"><div class="t-nv-ln-table"><div><a href="../regex_search.html" title="cpp/regex/regex search"><span class="t-lines"><span>regex_search</span></span></a></div><div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx11">(C++11)</span></span></span></div></div></td></tr>
<tr class="t-nv"><td colspan="5"><div class="t-nv-ln-table"><div><a href="../regex_replace.html" title="cpp/regex/regex replace"><span class="t-lines"><span>regex_replace</span></span></a></div><div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx11">(C++11)</span></span></span></div></div></td></tr>
<tr class="t-nv-h1"><td colspan="5"> 迭代器</td></tr>
<tr class="t-nv"><td colspan="5"><div class="t-nv-ln-table"><div><a href="../regex_iterator.html" title="cpp/regex/regex iterator"><span class="t-lines"><span>regex_iterator</span></span></a></div><div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx11">(C++11)</span></span></span></div></div></td></tr>
<tr class="t-nv"><td colspan="5"><div class="t-nv-ln-table"><div><a href="../regex_token_iterator.html" title="cpp/regex/regex token iterator"><span class="t-lines"><span>regex_token_iterator</span></span></a></div><div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx11">(C++11)</span></span></span></div></div></td></tr>
<tr class="t-nv-h1"><td colspan="5"> 异常</td></tr>
<tr class="t-nv"><td colspan="5"><div class="t-nv-ln-table"><div><a href="../regex_error.html" title="cpp/regex/regex error"><span class="t-lines"><span>regex_error</span></span></a></div><div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx11">(C++11)</span></span></span></div></div></td></tr>
<tr class="t-nv-h1"><td colspan="5"> 特性</td></tr>
<tr class="t-nv"><td colspan="5"><div class="t-nv-ln-table"><div><a href="../regex_traits.html" title="cpp/regex/regex traits"><span class="t-lines"><span>regex_traits</span></span></a></div><div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx11">(C++11)</span></span></span></div></div></td></tr>
<tr class="t-nv-h1"><td colspan="5"> 常量</td></tr>
<tr class="t-nv"><td colspan="5"><div class="t-nv-ln-table"><div><a href="../syntax_option_type.html" title="cpp/regex/syntax option type"><span class="t-lines"><span>syntax_option_type</span></span></a></div><div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx11">(C++11)</span></span></span></div></div></td></tr>
<tr class="t-nv"><td colspan="5"><div class="t-nv-ln-table"><div><a href="../match_flag_type.html" title="cpp/regex/match flag type"><span class="t-lines"><span>match_flag_type</span></span></a></div><div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx11">(C++11)</span></span></span></div></div></td></tr>
<tr class="t-nv"><td colspan="5"><div class="t-nv-ln-table"><div><a href="../error_type.html" title="cpp/regex/error type"><span class="t-lines"><span>error_type</span></span></a></div><div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx11">(C++11)</span></span></span></div></div></td></tr>
<tr class="t-nv-h1"><td colspan="5"> 正则表达式文法</td></tr>
<tr class="t-nv"><td colspan="5"><div class="t-nv-ln-table"><div><a href="../ecmascript.html" title="cpp/regex/ecmascript"><span class="t-lines"><span>Modified ECMAScript-262</span></span></a></div><div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx11">(C++11)</span></span></span></div></div></td></tr>
</table></div><div></div></div></div></div><div class="t-navbar-sep"> </div><div class="t-navbar-head"><a href="../basic_regex.html" title="cpp/regex/basic regex"><tt>std::basic_regex</tt></a><div class="t-navbar-menu"><div><div><table class="t-nv-begin" cellpadding="0" style="">
<tr class="t-nv-h1"><td colspan="5"> 成员函数</td></tr>
<tr class="t-nv"><td colspan="5"><div class="t-nv-ln-table"><div><a href="basic_regex.html" title="cpp/regex/basic regex/basic regex"><span class="t-lines"><span>basic_regex::basic_regex</span></span></a></div></div></td></tr>
<tr class="t-nv"><td colspan="5"><div class="t-nv-ln-table"><div><a href="~basic_regex.html" title="cpp/regex/basic regex/~basic regex"><span class="t-lines"><span>basic_regex::~basic_regex</span></span></a></div></div></td></tr>
<tr class="t-nv"><td colspan="5"><div class="t-nv-ln-table"><div><a href="operator%3D.html" title="cpp/regex/basic regex/operator="><span class="t-lines"><span>basic_regex::operator=</span></span></a></div></div></td></tr>
<tr class="t-nv"><td colspan="5"><div class="t-nv-ln-table"><div><a href="assign.html" title="cpp/regex/basic regex/assign"><span class="t-lines"><span>basic_regex::assign</span></span></a></div></div></td></tr>
<tr class="t-nv-h2"><td colspan="5"> 观察器</td></tr>
<tr class="t-nv"><td colspan="5"><div class="t-nv-ln-table"><div><a href="mark_count.html" title="cpp/regex/basic regex/mark count"><span class="t-lines"><span>basic_regex::mark_count</span></span></a></div></div></td></tr>
<tr class="t-nv"><td colspan="5"><div class="t-nv-ln-table"><div><a href="flags.html" title="cpp/regex/basic regex/flags"><span class="t-lines"><span>basic_regex::flags</span></span></a></div></div></td></tr>
<tr class="t-nv-h2"><td colspan="5"> 本地环境</td></tr>
<tr class="t-nv"><td colspan="5"><div class="t-nv-ln-table"><div><a href="getloc.html" title="cpp/regex/basic regex/getloc"><span class="t-lines"><span>basic_regex::getloc</span></span></a></div></div></td></tr>
<tr class="t-nv"><td colspan="5"><div class="t-nv-ln-table"><div><a href="imbue.html" title="cpp/regex/basic regex/imbue"><span class="t-lines"><span>basic_regex::imbue</span></span></a></div></div></td></tr>
<tr class="t-nv-h2"><td colspan="5"> 修改器</td></tr>
<tr class="t-nv"><td colspan="5"><div class="t-nv-ln-table"><div><a href="swap.html" title="cpp/regex/basic regex/swap"><span class="t-lines"><span>basic_regex::swap</span></span></a></div></div></td></tr>
<tr class="t-nv-h2"><td colspan="5"> 常量</td></tr>
<tr class="t-nv"><td colspan="5"><div class="t-nv-ln-table"><div><strong class="selflink"><span class="t-lines"><span>basic_regex 常量</span></span></strong></div></div></td></tr>
<tr class="t-nv-h1"><td colspan="5"> 非成员函数</td></tr>
<tr class="t-nv"><td colspan="5"><div class="t-nv-ln-table"><div><a href="swap2.html" title="cpp/regex/basic regex/swap2"><span class="t-lines"><span>swap<span class="t-dsc-small">(std::basic_regex)</span></span></span></a></div></div></td></tr>
<tr class="t-nv-h1"><td colspan="5"> <a href="deduction_guides.html" title="cpp/regex/basic regex/deduction guides">推导指引</a><span class="t-mark-rev t-since-cxx17">(C++17)</span></td></tr>
</table></div><div></div></div></div></div><div class="t-navbar-sep"> </div></div>
<table class="t-dcl-begin"><tbody>
<tr class="t-dsc-header">
<td> <div>定义于头文件 <code><a href="../../header/regex.html" title="cpp/header/regex">&lt;regex&gt;</a></code>
 </div></td>
<td></td>
<td></td>
</tr>
<tr class="t-dcl">
<td class="t-dcl-nopad"> <div><span class="mw-geshi cpp source-cpp"><span class="kw4">static</span> <span class="kw4">constexpr</span> <a href="../syntax_option_type.html"><span class="kw2027">std::<span class="me2">regex_constants</span><span class="sy4">::</span><span class="me2">syntax_option_type</span></span></a> icase <span class="sy1">=</span><br>
<p>    <a href="../syntax_option_type.html"><span class="kw2028">std::<span class="me2">regex_constants</span><span class="sy4">::</span><span class="me2">icase</span></span></a><span class="sy4">;</span><br>
<span class="kw4">static</span> <span class="kw4">constexpr</span> <a href="../syntax_option_type.html"><span class="kw2027">std::<span class="me2">regex_constants</span><span class="sy4">::</span><span class="me2">syntax_option_type</span></span></a> nosubs <span class="sy1">=</span><br>
    <a href="../syntax_option_type.html"><span class="kw2029">std::<span class="me2">regex_constants</span><span class="sy4">::</span><span class="me2">nosubs</span></span></a><span class="sy4">;</span><br>
<span class="kw4">static</span> <span class="kw4">constexpr</span> <a href="../syntax_option_type.html"><span class="kw2027">std::<span class="me2">regex_constants</span><span class="sy4">::</span><span class="me2">syntax_option_type</span></span></a> optimize <span class="sy1">=</span><br>
    <a href="../syntax_option_type.html"><span class="kw2030">std::<span class="me2">regex_constants</span><span class="sy4">::</span><span class="me2">optimize</span></span></a><span class="sy4">;</span><br>
<span class="kw4">static</span> <span class="kw4">constexpr</span> <a href="../syntax_option_type.html"><span class="kw2027">std::<span class="me2">regex_constants</span><span class="sy4">::</span><span class="me2">syntax_option_type</span></span></a> collate <span class="sy1">=</span><br>
    <a href="../syntax_option_type.html"><span class="kw2031">std::<span class="me2">regex_constants</span><span class="sy4">::</span><span class="me2">collate</span></span></a><span class="sy4">;</span><br>
<span class="kw4">static</span> <span class="kw4">constexpr</span> <a href="../syntax_option_type.html"><span class="kw2027">std::<span class="me2">regex_constants</span><span class="sy4">::</span><span class="me2">syntax_option_type</span></span></a> ECMAScript <span class="sy1">=</span><br>
    <a href="../syntax_option_type.html"><span class="kw2032">std::<span class="me2">regex_constants</span><span class="sy4">::</span><span class="me2">ECMAScript</span></span></a><span class="sy4">;</span><br>
<span class="kw4">static</span> <span class="kw4">constexpr</span> <a href="../syntax_option_type.html"><span class="kw2027">std::<span class="me2">regex_constants</span><span class="sy4">::</span><span class="me2">syntax_option_type</span></span></a> basic <span class="sy1">=</span><br>
    <a href="../syntax_option_type.html"><span class="kw2033">std::<span class="me2">regex_constants</span><span class="sy4">::</span><span class="me2">basic</span></span></a><span class="sy4">;</span><br>
<span class="kw4">static</span> <span class="kw4">constexpr</span> <a href="../syntax_option_type.html"><span class="kw2027">std::<span class="me2">regex_constants</span><span class="sy4">::</span><span class="me2">syntax_option_type</span></span></a> extended <span class="sy1">=</span><br>
    <a href="../syntax_option_type.html"><span class="kw2034">std::<span class="me2">regex_constants</span><span class="sy4">::</span><span class="me2">extended</span></span></a><span class="sy4">;</span><br>
<span class="kw4">static</span> <span class="kw4">constexpr</span> <a href="../syntax_option_type.html"><span class="kw2027">std::<span class="me2">regex_constants</span><span class="sy4">::</span><span class="me2">syntax_option_type</span></span></a> awk <span class="sy1">=</span><br>
    <a href="../syntax_option_type.html"><span class="kw2035">std::<span class="me2">regex_constants</span><span class="sy4">::</span><span class="me2">awk</span></span></a><span class="sy4">;</span><br>
<span class="kw4">static</span> <span class="kw4">constexpr</span> <a href="../syntax_option_type.html"><span class="kw2027">std::<span class="me2">regex_constants</span><span class="sy4">::</span><span class="me2">syntax_option_type</span></span></a> grep <span class="sy1">=</span><br>
    <a href="../syntax_option_type.html"><span class="kw2036">std::<span class="me2">regex_constants</span><span class="sy4">::</span><span class="me2">grep</span></span></a><span class="sy4">;</span><br>
<span class="kw4">static</span> <span class="kw4">constexpr</span> <a href="../syntax_option_type.html"><span class="kw2027">std::<span class="me2">regex_constants</span><span class="sy4">::</span><span class="me2">syntax_option_type</span></span></a> egrep <span class="sy1">=</span><br>
</p>
    <a href="../syntax_option_type.html"><span class="kw2037">std::<span class="me2">regex_constants</span><span class="sy4">::</span><span class="me2">egrep</span></span></a><span class="sy4">;</span></span></div></td>
<td class="t-dcl-nopad">  </td>
<td class="t-dcl-nopad">  </td>
</tr>
<tr class="t-dcl t-since-cxx17">
<td> <div><span class="mw-geshi cpp source-cpp"><span class="kw4">static</span> <span class="kw4">constexpr</span> <a href="../syntax_option_type.html"><span class="kw2027">std::<span class="me2">regex_constants</span><span class="sy4">::</span><span class="me2">syntax_option_type</span></span></a> multiline <span class="sy1">=</span><br>
    std<span class="sy4">::</span><span class="me2">regex_constants</span><span class="sy4">::</span><span class="me2">multiline</span><span class="sy4">;</span></span></div></td>
<td class="t-dcl-nopad">  </td>
<td> <span class="t-mark-rev t-since-cxx17">(C++17 起)</span> </td>
</tr>
<tr class="t-dcl-sep"><td></td><td></td><td></td></tr>
</tbody></table>
<p><span class="t-lc"><a href="../basic_regex.html" title="cpp/regex/basic regex">std::basic_regex</a></span> 定义数个掌控通用正则表达式语法的常量。
</p><p>这些常量复制自 <span class="t-c"><span class="mw-geshi cpp source-cpp">std<span class="sy4">::</span><span class="me2">regex_constants</span></span></span> ：
</p>
<table class="t-dsc-begin">

<tr class="t-dsc-sep">
<td colspan="2">  
</td></tr>
<tr class="t-dsc-hitem">
<td> 值
</td>
<td> 效果
</td></tr>


<tr class="t-dsc">
<td>  <code>icase</code>
</td>
<td> 应当以不考虑大小写进行字符匹配。
</td></tr>

<tr class="t-dsc">
<td>  <code>nosubs</code>
</td>
<td> 进行匹配时，将所有被标记的子表达式 <code><b>(<span class="t-spar">expr</span>)</b></code> 当做非标记的子表达式 <code><b>(?:<span class="t-spar">expr</span>)</b></code> 。不将匹配存储于提供的 <span class="t-lc"><a href="../regex_match.html" title="cpp/regex/regex match">std::regex_match</a></span> 结构中，且 <code>mark_count()</code> 为零
</td></tr>

<tr class="t-dsc">
<td>  <code>optimize</code>
</td>
<td> 指示正则表达式引擎进行更快的匹配，带有令构造变慢的潜在开销。例如这可能表示将非确定 FSA 转换为确定 FSA 。
</td></tr>

<tr class="t-dsc">
<td>  <code>collate</code>
</td>
<td> 形如 <i>"[a-b]"</i> 的字符范围将对本地环境敏感。
</td></tr>

<tr class="t-dsc">
<td>  <code>multiline</code> <span class="t-mark-rev t-since-cxx17">(C++17)</span>
</td>
<td> 若选择 ECMAScript 引擎，则指定 <code>^</code> 应该匹配行首，而 <code>$</code> 应该匹配行尾。
</td></tr>

<tr class="t-dsc">
<td>  <code>ECMAScript</code>
</td>
<td> 使用<a href="../ecmascript.html" title="cpp/regex/ecmascript">改 ECMAScript 正则表达式文法</a>
</td></tr>

<tr class="t-dsc">
<td>  <code>basic</code>
</td>
<td> 使用基本 POSIX 正则表达式文法（<a rel="nofollow" class="external text" href="http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap09.html#tag_09_03">文法文档</a>）。
</td></tr>

<tr class="t-dsc">
<td>  <code>extended</code>
</td>
<td> 使用扩展 POSIX 正则表达式文法（<a rel="nofollow" class="external text" href="http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap09.html#tag_09_04">文法文档</a>）。
</td></tr>

<tr class="t-dsc">
<td>  <code>awk</code>
</td>
<td> 使用 POSIX 中 <i>awk</i> 工具所用的正则表达式文法（<a rel="nofollow" class="external text" href="http://pubs.opengroup.org/onlinepubs/9699919799/utilities/awk.html#tag_20_06_13_04">文法文档</a>）。
</td></tr>

<tr class="t-dsc">
<td>  <code>grep</code>
</td>
<td> 使用 POSIX 中 <i>grep</i> 工具所用的正则表达式文法。这等效于 <code>basic</code> 选项附带作为另一种分隔符的换行符 '\n' 。
</td></tr>

<tr class="t-dsc">
<td>  <code>egrep</code>
</td>
<td> 使用 POSIX 中 <i>grep</i> 工具带 <i>-E</i> 选项所用的正则表达式文法。这等效于 <code>extended</code> 附带 '|' 之外的作为另一种分隔符的换行符 '\n' 。
</td></tr>
</table>
<p><code>ECMAScript</code>, <code>basic</code>, <code>extended</code>, <code>awk</code>, <code>grep</code>, <code>egrep</code> 必须选取至多一个文法选项。若不选取文法选项，则设定为选取 <code>ECMAScript</code> 。其他选项作为修饰符工作，从而 <span class="t-c"><span class="mw-geshi cpp source-cpp"><a href="http://zh.cppreference.com/w/cpp/regex/basic_regex"><span class="kw2000">std::<span class="me2">regex</span></span></a><span class="br0">(</span><span class="st0">"meow"</span>, std<span class="sy4">::</span><span class="me2">regex</span><span class="sy4">::</span><span class="me2">icase</span><span class="br0">)</span></span></span> 等价于 <span class="t-c"><span class="mw-geshi cpp source-cpp"><a href="http://zh.cppreference.com/w/cpp/regex/basic_regex"><span class="kw2000">std::<span class="me2">regex</span></span></a><span class="br0">(</span><span class="st0">"meow"</span>, std<span class="sy4">::</span><span class="me2">regex</span><span class="sy4">::</span><span class="me2">ECMAScript</span><span class="sy3">|</span>std<span class="sy4">::</span><span class="me2">regex</span><span class="sy4">::</span><span class="me2">icase</span><span class="br0">)</span></span></span>
</p>
<h3><span class="mw-headline" id=".E5.8F.82.E9.98.85">参阅</span></h3>
<table class="t-dsc-begin">

<tr class="t-dsc">
<td>  <div class="t-dsc-member-div"><div><a href="../syntax_option_type.html" title="cpp/regex/syntax option type"> <span class="t-lines"><span>syntax_option_type</span></span></a></div><div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx11">(C++11)</span></span></span></div></div>
</td>
<td>  控制正则表达式行为的通用选项 <br> <span class="t-mark">(typedef)</span> </td></tr>
</table>

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